var imgArray = new Array();

function preLoad ()
{
    var a = preLoad.arguments;

    for ( i = 0 ; i < a.length ; i++ )
    {
        imgArray[i] = new Image();
        imgArray[i].src = a[i];
    }
}

function swapImage ( imgObj , newSrc )
{
    imgObj.oSrc = imgObj.src;
    imgObj.src = newSrc;
}

function restoreImage ( imgObj )
{
    imgObj.src = imgObj.oSrc;
}